Polyamide filaments containing high viscosity antistatic agents

ABSTRACT

Static-resistant polyamide fibers are produced by dispersing from 0.1 to 20 percent by weight of a modified polyalkoxylated hydrogenated castor oil (castor wax) into the polyamide melt prior to filament formation. The modified castor wax is the addition product of castor wax and a diepoxide compound having two ethoxyline groups AS TERMINAL GROUPS. The modified castor wax has a higher melt viscosity than the corresponding unmodified castor wax which enables better dispersion thereof in the polyamide melt. As a result, polyamide fibers containing the modified castor wax are more easily processed and are of higher quality.

United States Patent Crovatt, Jr. et al. [451 May 30, 1972 [541 POLYAMIDE FILAMENTS 3,388,104 6/1968 Crovatt ..260/78 s CONTAINING HIGH VISCOSITY m Ex dD d QNT] NT mary ammer-Harol .An erson STATIC AGE S Attorney-Stanley M. Tarter, John W. Whisler and Elmer J. [72] inventors: Lawrence W. Crovatt, Jr., Gulf Breeze; Fischer Ullman C. Garrett, Jr., Pensacola, both of Fla. [57] ABSTRACT [73] Assignee: Monsanto Company, St. Louis, Mo. Static-resistant polyarnide fibers are produced by dispersing from 0.l to 20 percent by weight of a modified polyalkoxy- [22] Filed 1970 lated hydrogenated castor oil (castor wax) into the polyamide 1 App], 3, 1 melt prior to filament formation. The modified castor wax is the addition product of castor wax and a diepoxide compound [52] US. Cl. ..260/78 S, 260/ l 8 N, 260/47 ED, C)

260/78 A, 260/78 L, 260/830 P, 260/857 R, having two ethoxyltne groups (no. CH CH) as 260 357 PG terminal groups. The modified castor wax has a higher melt [51] lnt.Cl ..C08 20/38 iscosity than the corresponding unmodified castor wax [58] Field otSearch.... ...260/78 R, 78 S, 78 A, 78 L, which enables better dispersion thereof in the polyamide 260/18 N, 47 EP, 830 P, 857 PE melt. As a result, polyamide fibers containing the modified castor wax are more easily processed and are of higher [56] References Cited quality.

UNITED STATES PATENTS 3,226,178 12/1965 Walker ..8/l65 7Clalms,No Drawings BACKGROUND OF THE INVENTION Polyamide fibers containing castor wax are described in Us. Pat. No. 3,388,104, issued June ll, 1968 to L. W. Crovatt, Jr.

Castor wax is easily prepared, by reacting hydrogenated castor oil with the appropriate number or moles of alkylene oxide per mole of oil. However, since slow reaction rates and prolonged heating times are encountered in attempting to add more than about 250 moles of alkylene oxide onto the hydrogenated castor oil molecule, high alkylene oxide-com taining castor waxes are costly and are of inferior quality. One disadvantage in using castor wax having less than about 250 moles of alkylene oxide in its molecule to produce static-resistant polyamide fibers by melt spinning processes is that this castor wax does not have a sufficiently high melt viscosity to disperse uniformly in the polyamide melt.

Non-uniform dispersion of castor wax in the polyamide melt results in poor processability of the filaments (e.g. filaments discontinuities are encountered) and in filaments of reduced quality (e.g. the filaments are of non-uniform cross-section and the antistatic property thereof is reduced).

An object of the invention is to provide castor wax-containing polyamide filaments of improved quality.

7 SUMMARY OF THE INVENTION The above-mentioned objects of the invention are accomplished by providing a modified castor wax which is the addition product of a poly-alkoxylated hydrogenated castor oil (castor wax) of the formula:

CHzO p (CH2) m H e ra wherein x y +z is between 50 and about 250 and R is a C to C alkylene radical, and a compound containing carbon, hydrogen and oxygen atoms and having two ethoxyline groups O ofticm-cficm 2. diglycidyl ether having the formula 0 0 vii, vnvmoumcfi rm 3. diglycidyl others of:

a. mononuclcur and polynucleur dihydroxy phenols; b. diols; and

c. poly(alkylene ethers), wherein the alkylene radicals has from two to four carbon atoms. These diglycidyl ethers may be represented by the formula:

wherein R is the hydrocarbon residue of a diol or a diphenol or the radical wherein R is a C, to C.: alkylene radical and n is an integer from i to about 350.

4. poly(diglycidyl ethers) of the compounds described under paragraph 3 which may be represented by the formula ethers include:

' 0H -CH2OH n and m are integers from 1 to 10. Diols which may be used to prepare the diglycidyl ethers include: ethylene diol, 2,3-butanediol, 1,6-hexanediol, etc. (e.g. alkylene and alkane diols having two to 12 carbon atoms. Poly(alkylene ethers) which may be used to prepare the diglycidyl ethers include: polyethylene glycols, polypropylene glycols and copolymers thereof, wherein the poly(all ylene ethers) have a molecular weight between about 106 and 10,000. The diglycidyl ether of bisphenol A is a preferred diepoxide for use in carrying out the invention since it is inexpensive and commercially available.

The amount of diepoxide reacted with the castor wax may vary over a wide range depending upon the molecular weights thereof and the melt viscosity desired for the modified castor wax. in general, a mole ratio within the range of from 2:3 to 5:1, castor wax to diepoxide, may be employed. Good results are attained, for example, by reacting castor wax containing 200 moles of ethylene oxide per mole of wax with from 3 to 10 grams of Epon 828 per grants of the castor wax.

The reaction occurring between the diepoxide and castor wax molecules is one of addition in which epoxy groups react wi h hydroxy groups to form and Where The invention provides an economical method for increasing the melt viscosity of castor waxes without sacrificing the quality or characteristics thereof, thereby enabling easy and 5 uniform dispersion thereof into polyamide melts. The polyamide melts can then be readily melt-spun into high quality static-resistant filaments.

PREFERRED EMBODIMENTS OF THE INVENTION The following examples are given to further illustrate the invention. In the examples 200 E0 castor wax refers to the compound of formula I when x y z 200.

EXAIVIPLE I Two products, indicated as A and B in Table l, were prepared by reacting 200 E0 castor wax containing 0.01 milliequivalents/grarn of KOl-I catalyst with (a) 3.27 grams of diglycidyl ether of bis(4-hydroxyphenyl)-dimethylmethane per 100 grams of 200 E0 castor wax (product A) and with (b) 4.42 grams of the diglycidyl ether per 100 grams of 200 E0 castor wax (product B). The reactions were carried out in stirred reaction vessels under an inert gas blanket at 130 C.

. for 3 hours. The products after cooling to 95 C. were neutralized using an aqueous 85% phosphoric acid solution. Each of the products were then filtered to remove insoluble potassium phosphate salm. The melt viscosity of the products and of 200 E0 castor wax is shown in Table 1.

"Brcokfield LVF viscometer. No. 2 spindle at 30 rpm. "cps centipoises EXAMPLE II This example illustrates the preparation of polyhexamethylene adipamide (nylon 66) filaments containing 7.5 percent by weight of 200 E0 castor wax having a melt viscosity of 3 l0 cps.

Nylon 66 flake is fed into an extruder and 7.5 percent by weight of 200 E0 castor wax was injected into the melt section of the extruder immediately prior to a mix section thereof. The resulting mixture was then spun into filaments. Poor wax dispersion was indicated by poor spinning performance due to excessive filament discontinuities or drips. In addition, the cross-section of some of the filaments were difierent from the cross-section of other of the filaments, i.e., the filament-tofilament cross-section was not uniform.

EXAMPLE III EXAMPLE IV The yarns of Examples ll and [II were each laundered in a conventional electric washing (Sears) machine with commercially available detergent (Tide). After laundering the percent wax retained in each yarn was determined by extracting the remaining wax and comparing this amount to the amount present before laundering (7.5 percent by weight). The wax retained in the yarn of Example II, which contained 7.5 percent by weight 200 E0 castor'wax, was 60 percent, whereas the wax retained in the yarn of Example III, which contained 7.5 percent by weight of product A, was 78 percent.

The results in the examples show that the castor wax/diepoxide reaction products described herein are easily dispersed in nylon melt to provide a mixture that is capable of being melt spun into high quality filaments.

The castor wax/diepoxide reaction products may be incorporated into any polycarbonamide. The polycarbonamides are well known in the art and are generally prepared by heating either (2) substantially equimolecular proportions of a diamine and a dicarboxylic acid or (b) various amino acids or the amide-fomiing derivatives thereof (e.g. lactams) until the material has polymerized to the fiber-forming stage. The diamines are generally of the formula NH,(CH,),NH,, wherein n is at least 2 and preferably 4 to 12; the dicarboxylic acids are generally of the formula HOOCR COOH, wherein R is a divalent hydrocarbon radical having a chain length of at least two carbon atoms and preferably four to 10 carbon atoms; the amino acids are generally of the fonnula NI-I (CH )BnCOOH, wherein n is 3 to I1 and the amide-forming derivatives thereof commonly employed are the lactams of the formula Representative polycarbonamides include polyhexamethylene adipamide, polyhexamethylene sebacamide, polycaprolactam, etc. Polycarbonamides of the foregoing description are characterized in containing recurring carbonamide linkages separated from one another by at least twocarbon atoms. The invention has been described with reference to castor wax prepared by reacting hydrogenated castor oil with a molar excess (50:1 to 250:1) of ethylene oxide. Ethylene oxide is preferred due to the better performance and commercial availability thereof. However, other C to C. alkylene oxides can also be used to prepare the castor wax, such as propylene oxide or butylene oxide or mixtures of the C, to C alkylene oxides.

We claim 1. A polycarbonamide static-resistant filament containing from 2 to 15 percentby weight of the addition product obtained by reacting a polyalkoxylated hydrogenated castor oil of the formula:

wherein R is a C, to C alkylene radical and x, y and z are integers, the sum of which is between 50 and about 250, and a compound selected from the group consisting of butadiene dioxide, diglycidyl ether and diglycidyl ethers of the formula where R is the hydrocarbon residue of a diol or diphenol and n is zero or an integer from 1 to 50, in a mole ratio of from 2:3 to 5:1, said castor oil to said compound, wherein the reaction occurring between said castor oil and said compound is an ad dition reaction in which hydroxy groups of said castor oil react O with rou s of said corn ound CQCH- g p r p to form linkages. 

2. The filament of claim 1 wherein said compound is the diglycidyl ether of bis(4-hydroxyphenyl) dimethylmethane.
 3. The filament of claim 1 wherein said compound is butadiene dioxide.
 4. The filament of claim 1 wherein said compound is the diglycidyl ether of polyethylene glycol in which the glycol has a molecular weight between about 150 and about 10,000.
 5. The filament of claim 2 wherein the polycarbonamide is polyhexamethylene adipamide.
 6. The filament of claim 3 wherein the polycarbonamide is polyhexamethylene adipamide.
 7. The filament of claim 4 wherein the polycarbonamide is polyhexamethylene adipamide. 